Stock-Based Compensation (Details) - $ / shares	6 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, number granted	548,398	932,678
Stock options, weighted average grant date fair value	$ 18.59	$ 9.36
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Expected life of option (years)	6 years	6 years 6 months
Risk-free interest rate	1.35%	0.60%
Expected volatility of the Company's stock	27.80%	27.60%
Expected dividend yield on the Company's stock	1.71%	2.28%
Stock options \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	2 years
Stock options \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, number granted	19,768	35,254
Equity instruments other than options, weighted average grant date fair value	$ 18.59	$ 9.36
Restricted stock/units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, number granted	1,267,490	1,697,257
Equity instruments other than options, weighted average grant date fair value	$ 78.50	$ 46.20
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, number granted	482,030	410,934
Equity instruments other than options, weighted average grant date fair value	$ 82.88	$ 50.53
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Risk-free interest rate	0.99%	0.20%
Expected volatility of the Company's stock	30.00%	30.90%

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Net number of share options (or share units) granted during the period.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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